Abstract—The increasing demand for bandwidth in data communication motivates the development of high-speed and low-cost optical links. In this paper, Sub-Carrier Multiplexed (SCM) Radio over Fiber System (ROF) with modified DPSK modulation technique has been investigated by using a relatively new type of laser called Vertical-Cavity Surface-Emitting Laser (VCSEL). A simulation model has been developed to extend both transmission distance up to 200 Km and bit rate 20Gbp/s with single mode fiber (SMF). Using various dispersion compensation techniques namely FBG (Fiber Bragg Grating), OPC (Optical Phase Conjugation) and DCF (Dispersion compensating Fiber) lead to compensate the dispersion and enhance bit rate up to 20Gbps through SMF. EDFA (Erbium-doped fiber amplifier) used to amplify signals. The performance of various dispersion compensation techniques has been studied through software OptiSystem Version 14.1. BER (Bit Error Rate) and Quality Factor (QF) have been observed to analyze the performance of these various compensation techniques to mitigate dispersion caused in the system. 
 

Index Terms—ROF, DPSK, Q-factor, SCM, VCSEL, DCF, FBG, OPC, SMF and BER

Cite: Amira M. Ismail, Abd El-Naser A. Mohamed, Ahmed Nabih Zaki Rashed, and Mohamed S. F. Tabbour, "ROF Communication System Performance Enhancement Using Both Modified Differential Phase Shift Keying (DPSK) and Sub-Carrier Multiplexing Technique," Journal of Communications, vol. 14, no. 1, pp. 58-63, 2018. Doi: 10.12720/jcm.14.1.58-63